The present invention provides new cyclopentylalkyl-nitriles and methods for applying to a substrate a fragrance made from such compounds.
Despite the common occurrence of five-membered carbon rings in perfumery ingredients, mainly of terpenic origin (e.g. campholenic aldehyde derivatives of sandalwood-type odor note) or resulting from a Diels-Alder condensation with inexpensive cyclopentadiene, very few of such structures contain an unsubstituted, isolated (i.e. not part of a polycyclic fused or spiro system) cyclopentyl, cyclopentenyl or cyclopentylidene radical. The following products are among the few examples of such perfumery raw materials: 
These compounds are also disclosed in EP 0 016 650, EP 0 770 671 and U.S. Pat. Nos. 4,280,934 and 4,338,458.
There is a renewed interest in floral fragrances. Therefore, an object of the present invention is to provide new perfumery ingredients exhibiting original, intense, diffusive and substantive (i.e. long-lasting) scents belonging to the floral family.
One embodiment of the invention is a compound of formula I: 
wherein
R1 and R3 are independently H or C1-3 alkyl, and R2 is H, C1-3 alkyl, methylene or ethylidene, with the proviso that R1 and R2 are not simultaneously H;
n is 0 or 1; and
- - - is a single or a double bond, wherein a maximum of two double bonds are present in the compound. These compounds possess very intense, mainly rosy and orris notes.
Another embodiment of the invention is a compound of formula II: 
wherein
A is selected from the group of CR4R5OH, CR4R5OC(O)R6, CO2R6, CN and C(O)R4;
R1, R3, R4, and R5 are independently H or C1-3-alkyl;
R2 is H, C1-3-alkyl, methylene, or ethylidene;
R6 is H, C1-3 alkyl, C2-4 alkenyl, or alkinyl;
n is 0 or 1; and
- - - is a single or a double bond, wherein a maximum of two double bonds are present. These compounds possess interesting olfactory properties. The odors are mainly floral, e.g. lily of the valley, orris or ylang-ylang and fruity, e.g. citrus. They are intense, diffusive and long lasting. All compounds of the general formula II have substantive odors, a quality crucial for fictional perfumery.
As noted above, the invention provides a compound of formula I: 
wherein
R1 and R3 are independently H, or C1-3 alkyl, and R2 is H, C1-3 alkyl, methylene or ethylidene; with the proviso that R1 and R2 are not simultaneously H;
n is 0 or 1; and
- - - is a single or a double bond, wherein a maximum of two double bonds are present in the compound.
The invention also provides a method of using the compounds of formula II 
wherein
A is selected from the group of CR4R5OH, CR4R5OC(O)R6, CO2R6, CN or C(O)R4;
R1, R3, R4, and R5 are independently H or C1-3-alkyl;
R2 is H, C1-3-alkyl, methylene or ethylidene;
R6 is H, C1-3-alkyl, C2-4-alkenyl, or alkinyl;
n is 0 or 1; and
- - - is a single or a double bond, wherein a maximum of two double bonds are present.
The heteroatoms in all compounds of formula I and II of the present invention are in a more remote position relative to the lipophilic cyclopentane ring than the oxygen atoms in the corresponding known perfumery ingredients.
The compounds of formula II may be used to impart odor to any perfumery composition, such as for example fine and functional perfumery, e.g. perfumes, fine fragrance accords or detergents, fabric softeners, shower gels, soaps, cosmetics, scented candles, and the like.
The compounds of formula I are new. The following is an exemplary list of compounds of formula II which are also new:
5-Cyclopentyl-3-methylpent-4-en-1-ol
5-Cyclopentyl-3-methylpent-4-enal
5-Cyclopentyl-3-methylpent-4-en-1-yl acetate
5-Cyclopentyl-3-methylpentan-1-ol
4-Cyclopentylpentan-1-ol
4-Cyclopentylpent-1-yl propanoate
4-Cyclopentylpentanal
Ethyl-4-cyclopentylpentanoate
5-Cyclopentylhexan-2-one
5-Cyclopentylhexanal
5-Cyclopentylhexan-1-ol
5-(2-Methylcyclopent-1-enyl)pentan-1-ol
5-(5-Methylcyclopent-1-enyl)pentan-1-ol
4-Cyclopentylidenebutan-1-ol
6-Cyclopentyl-3-methylhexan-3-ol
5-(Cyclopent-1-enyl)-2-methylpentan-2-ol
5-Cyclopentylpentan-2-ol
5-Cyclopentylidene-2-methylpentan-2-ol
5-Cyclopentylidenepent-2-yl propanoate
The following compounds of formula I are preferred:
5-Cyclopentyl-3-methylpentanenitrile
4-Cyclopentylpentanenitrile
5-Cyclopentylhexanenitrile
5-Cyclopentylidenehexanenitrile
5-(Cyclopent-1-enyl)hexanenitrile
The compounds of formulae I and II may be prepared by different synthetic ways. For example, the five-membered ring may be introduced with commercially available starting materials (cyclopentanone, cyclopentadiene, cyclopentylhalogenide and derivatives) or, prepared by 1,4-dihalogenobutane-derived Grignard reagent addition to lactones. Among the best methods for synthesizing functionalized cyclopentyl-, cyclopentenyl- or cyclopentylidene-alkanes are the cyclopentadienyl anion addition to carbonyl groups, followed by a total or partial hydrogenation of the thus formed fulvene structure, as depicted in scheme I (See, e.g. Coe, J.; Vetelino, M. G.; Kemp, D. S. Tetrahedron Lett. 1994, 35, 6627). 
wherein xe2x80x9caxe2x80x9d is piperidine and xe2x80x9cbxe2x80x9d is hydrogenation.
The odorant compounds of formula II may be combined with numerous odorant ingredients of natural and/or synthetic origin, wherein the range of the natural odorants may include not only readily volatile, but also moderately and only slightly volatile components. The synthetic odorants may embrace representatives from practically all classes of substances. The following non-limiting list includes examples of known odorant compositions which may be combined with the compounds of the invention:
natural products such as tree moss absolute, basil oil, tropical fruit oils (such as bergamot oil, mandarin oil, etc.), mastix absolute, myrtle oil, palmarosa oil, galbanum oil, patchouli oil, petitgrain oil, wormwood oil, lavender oil, rose oil, jasmine oil, ylang-ylang oil, and the like;
alcohols such as farnesol, geraniol, linalool, nerol, phenylethyl alcohol, rhodinol, cinnamic alcohol, (Z)-hex-3-en-1-ol, menthol, xcex1-terpineol, and the like;
aldehydes such as citral, xcex1-hexyl cinnamaldehyde, LILIAL(copyright) (Givaudan Roure), hydroxycitronellal, methylnonylacet-aldehyde, phenylacetaldehyde, anisaldehyde, vanillin, and the like;
ketones such as allylionones, xcex1-ionone, xcex2-ionone, ISORALDEINE(copyright) (Givaudan Roure), methylionone, verbenone, nootkatone, geranylacetone, and the like;
esters such as allyl phenoxyacetate, benzyl salicylate, cinnamyl propionate, citronellyl acetate, decyl acetate, dimethylbenzylcarbinyl acetate, dimethylbenzylcarbinyl butyrate, ethyl acetoacetate, cis-3-hexenyl isobutyrate, cis-3-hexenyl salicylate, linalyl acetate, methyl dihydrojasmonate, styralyl propionate, vetiveryl acetate, benzyl acetate, geranyl acetate, and the like;
lactones such as xcex3-undecalactone, xcex4-decalactone, pentadecanolide, 12-oxahexadecanolide, and the like;
acetals such as Viridine (phenylacetaldehyde dimethylacetal), and the like; and
various components often used in perfumery such as indole, p-mentha-8-thiol-3-one, methyleugenol, eugenol, anethol, and the like.
The novel odorants harmonize particularly well with all other floral notes (lily of the valley, rose, orris, jasmine, ylang-ylang, narcissus notes, and the like), as well as with woody, chypre and animalic notes, tobacco-like and patchouli compositions, and the like.
The amount of a compound according to the present invention that may be combined with such odorant compositions may vary within wide limits ranging from a few parts per thousand in mass market products (e.g. cleaning or deodorant products) up to a few percent in alcoholic extracts for (fine) perfumery. In all cases, even in small amounts, the compounds of the present invention provide odorant compositions with intense floral notes with increased volume (strength, diffusivity) and substantivity of the odor. In particular, the manner in which the present compounds extend the diffusivity and the olfactory duration of such odorant compositions is remarkable.
There is no restriction regarding the type of fragrance formulations that may be combined with the compounds of the present invention. Nor is there a limitation on the destination of the actual finished product. Non-limiting examples of suitable formulations/finished products include eau de cologne, toilet water, scented water, perfume, cream, shampoo, deodorant, soap, detergent powder, household cleaner, fabric softener, and the like.
In the following examples, all compounds were identified by their 1H-NMR-, IR- and MS-spectra under the following conditions:
IR: Nicolet 510 FT-IR, neat, xcexd in cmxe2x88x921; 1H NMR: Bruker DPX-400 at 250 and 400 MHz; in CDCl3, if not otherwise stated; chemical shifts (d) in ppm downfield from TMS, coupling constants J in Hz; and MS and GC/MS: Finnigan MAT 212 (EI, 70 eV), intensities (in brackets) in % rel. to the base peak.
They were always purified by fractional distillation, or bulb-to-bulb distillation, if after flash chromatography (Merck silica gel 60; 230-400 mesh), and were olfactorily pure, colorless oils.
The following examples are provided to further illustrate the compounds of the present invention. These examples are illustrative only and are not intended to limit the scope of the invention in any way.